In some networking environments, communication networks may be formed when multiple interoperable nodes communicating over a shared medium detect the existence of other nodes. One example of such a network is a network that operates in accordance to the Media over Coax Alliance (“MoCA”) MAC/PHY Specification v. 1.0. In this network, nodes may function as “clients” or “slave” nodes, or as “master”/“network controller”/“network coordinator” (“NC”) nodes. A network will typically have a single NC node and any number of client nodes, and the NC node may transmit beacons and other control information to manage the network.
Upon power application or resetting, nodes may scan the available range of possible frequencies to determine where to operate, searching for signals from an NC node. If an NC node signal is found, indicating an existing network, a node may join the existing network. Joining a network involves a node following the protocol specified for network admission. Joining generally involves receiving network information transmitted by the NC node, determining time slots in which to transmit a network admission request, and sending a network admission request, including an identifying message on a designated time slot. The requesting node receives acknowledgement from the NC node for admission to the network.
If an existing network is not found, the node may establish a network at a specific frequency by operating as an NC node and waiting for other nodes to detect its presence and join the network. Where many nodes are nearly simultaneously scanning possible frequencies, it is possible that several nodes will fail to detect the existence of an established network and form a new network. Thus, multiple networks may be formed within the possible frequencies where it is intended or desired that a single network including all nodes is formed, such as within a home environment.